Noisy top end

hi. if someone can give me an idea, i have 2004 land rover discovery, and i hear a single ticking noise on top. i open valve covers, and i was thinking bad lifter. i can see nothing really broken, but i found one of the push rods bent. i inspected all of them, and i got new lifters and push rods only for one side. i put it together, runs fine, but half an hour after, the noise came back again. can somebody tell me something, please.

@ram123

Can you please clarify?

You replaced 1 push rod?

You replaced ALL of the lifters?

This may be old school thinking here, but I believe new lifters need to be primed before installation

i had the lifter in oil from day before i replaced only one side on the engine mean 8 lifters 8 push rods

@ram123

Okay. You primed the lifters.

Why didn’t you replace all of the lifters, if I may ask?

It could also be a lack of oil pressure due to engine wear or sludging which is plugging up oil galleys and cutting off or diminishing the oil supply to the valve lifters.

Valve train slack for whatever reason will also damage camshaft lobes.

do you know how much oil preasure should be

I do not know what the factory spec is but an estimate for warmed up engine could be around 30 PSI at idle and 50 or more at speed.

However, even if the lower end of the engine is good and the oil pressue is fine that does not mean that an oil galley to the engine top end is not plugged up to some degree.
The assumption could be that if the valve train under the valve covers and the lifter valley is heavily saturated with oil when you tore it apart the top end is getting enough oil.

well i didi not see much oil in top end when i took a part i m thinking doing eng flush i thank u for rour time.i hop i resolve this problem whit out spending too much money